In the hospital, particularly in the postoperative setting, pain is a primary concern of patients. Opioid analgesics have been used to treat postoperative pain since 1784 and parenteral morphine has been a primary treatment modality since the 1850s. While opioids are highly effective in the treatment of many painful conditions, they have side effects and dose-dependent risks including nausea, vomiting, constipation, urinary retention, sedation, and respiratory depression. Similarly, non steroidal anti-inflammatory drugs (NSAIDs), including the older non selective (dual inhibitor) products and newer cyclo-oxygenase (COX)-2 products, have a variety of unwanted side effects especially when used in the perioperative setting. Non selective NSAIDs are associated with platelet dysfunction and the potential for bleeding at the surgical site, upper gastrointestinal ulcers and bleeding, edema, hypertension, congestive heart failure, renal dysfunction, severe skin reactions such as Stevens-Johnson syndrome and toxic epidermal necrolysis, anaphylaxis, and most recently, an increased risk of thrombotic cardiovascular events.